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5.3 Mental Diseases
Many pollutants pass straight from the nose to the brain where they affect brain function. Air pollution correlates with inpatient admissions with organic brain syndrome, schizophrenia, major affective disorders, neurosis, behavioural disorder of childhood and adolescence, personality disorder and alcoholism231. Increases in the total number of psychiatric emergency room visits and in schizophrenia232 have been noted on days when air pollution has been high. Depression has also been linked to inhaled pollutants233,234. Clearly something very profound occurs when we pollute the air.
5.4 Violence and Crime
An increasing number of studies, including studies of murderers235, case-control and correlation studies13,94,236,237 and prospective studies96,238 have shown links between violence and heavy metals and these include lead, cadmium and manganese. The majority of the studies have investigated lead. Violence and crime have been associated with both increased body levels of lead and with increased levels of lead in the air. For instance Denno239 found early lead exposure was one of the most important predictors of disciplinary problems from ages 13 to 14, delinquency from ages 7 to 17 and adult criminal offences, from ages 18 to 22. Stretesky found an association between air lead levels and murder rates in US counties240. It is interesting that air lead levels were a much stronger predictor of both violent and property crime than unemployment, which has often been considered an important cause for crime241. The likely mechanism is that these substances alter neurotransmitters such as dopamine and serotonin and reduce impulse control.
This growing literature should serve as a warning about the dangers of allowing heavy metals to be emitted into the environment. Crime, especially violent crime, can have a dramatic effect on people’s quality of life. We need to consider the effect of incinerators, not only on health, but on education and on quality of life, including the impact of violence and crime.
6. High Risk Groups
The unborn child is the most vulnerable member of the human population. The foetus is uniquely susceptible to toxic damage and early exposures can have life changing consequences. Why is the foetus so vulnerable? There are two main reasons. Firstly most of these chemicals are fat soluble. The foetus has virtually no protective fat stores until very late pregnancy so the chemicals are stored in the only fatty tissues it has, namely its own nervous system and particularly the brain. Secondly many pollutants are actively transported across the placenta from the mother to the foetus. This occurs with heavy metals which the body mistakes for essential minerals. This is particularly critical for mercury where one tenth of women already have body stores of mercury which can lead to neurodevelopmental problems in the newborn242. Other factors that increase foetal susceptibility are higher rates of cell proliferation, lower immunological competence and decreased capacity to detoxify carcinogens and repair DNA243.
Safety limits currently do not take into account this increased risk to the foetus. Only 7% of high volume chemicals have been tested for neurodevelopmental toxicity244 and very few pollutants have been tested for teratogenicity.
During a narrow window of time, in the first 12 weeks in utero, the foetus’s body is affected by miniscule amounts of hormone measured in parts per trillion. Tiny amounts of chemicals can upset this delicate balance. It is now generally accepted that chemicals that are not toxic to an adult can have devastating effects on the newborn. Porterfield has shown that small amounts of chemicals such as dioxins and PCBs, at doses that are not normally regarded as toxic, can affect thyroid hormones and neurological development11. A single exposure is enough and timing is critical245. Small doses of oestrogenic chemicals can alter sexual development of the brain and the endocrine system246.
It is estimated that 5% of babies born in the USA have been exposed to sufficient pollutants to affect neurological development247. It has also been shown that exposure to oestrogenic chemicals affects immunity, reduces the immune response to vaccines, and is associated with a high incidence of middle ear and recurrent respiratory infections248. The amount of chemical that the baby takes in relates to the total persistent contaminants that have built up in the mother’s fat over her lifetime249. This will increase in areas around incinerators. Exposure to fine particulate pollution during pregnancy can have an adverse effect on the developing foetus and lead to impaired foetal growth74.
In July 2005, in a ground-breaking study250, researchers at two major laboratories in the USA looked at the body burden in the foetus. They reported an average of 200 industrial chemicals and pollutants (out of 413 tested) in the umbilical cord blood of 10 randomly chosen babies. These included 180 carcinogens, 217 chemicals that are toxic to the brain and nervous system and 208 that can cause birth defects and abnormal development in animals. A statement by scientists and paediatricians said that the report raised issues of substantial importance to public health, showed up gaping holes in the government’s safety net and pointed to the need for major reform to the nation’s laws that aim to protect the public from chemical exposures.
Two months later, scientists at the University of Groningen, released the results of a European study, commissioned by WWF and Greenpeace, on the foetal body burden. They tested for the presence of 35 chemicals in the umbilical cord blood of newborns251. At least five hazardous chemicals were found in all babies and some had as many as 14 different compounds. The report questioned the wisdom of allowing the foetus to be exposed to a complex mixture of persistent, bio-accumulative and bioactive chemicals at the most critical stage of life.
Incinerators can only have the effect of increasing the foetal body burden and their use is therefore a retrograde step for society. It is particularly important to apply the precautionary principle in issues that affect the foetus, infant and child.
6.2 The Breast-fed Infant
It is a major concern that breast milk, perhaps the greatest gift a mother can give for the future health of her child, has now become the most contaminated food on the planet, in terms of persistent organic pollutants252. In the USA studies of human breast milk have shown that 90% of samples contained a disturbing 350 chemicals. This was higher in industrialised areas showing that inhalation of these toxic substances is an important factor253. The dose taken in by a breast-feeding baby is 50 times higher than that taken in by an adult254.
The incinerator would add to the total load of chemicals in the mother’s fat and those toxins accumulated over a lifetime by the mother will then be transferred to the tiny body of her baby through her milk. Six months of breast feeding will transfer 20% of the mother’s lifetime accumulation of organochlorines to the child255. From 1979 one in four samples of breast milk have been found to be over the legal limit set for PCBs in commercial feeds249 and these are known to impair intellectual development 256-8. Contamination with persistent organic pollutants (POPs) in breast milk in animals has consistently shown structural, behavioural and functional problems in their offspring259. For instance, in monkeys it has shown that it decreases their ability to learn260-2. Polybrominated diphenyl ethers (PBDEs) are toxic chemicals which have been doubling in breast milk every five years, and have also been rapidly increasing in the waste fed to incinerators as they are now present in many common electrical and electronic goods. PBDEs cause cancer, birth defects, thyroid dysfunction and immune suppression.263,264 It is truly tragic that one of the few ways of removing these contaminants from the mother’s body is by breast-feeding.
Toxic and carcinogenic exposures in early life, including prenatal exposures, are more likely to lead to cancer than similar exposures later265-7. At the First International Scientific Conference of Childhood Leukaemia, held in September 2004, Professor Alan Preece suggested that pollutants crossing the placenta, were damaging the immune system and could be linked with soaring rates of leukaemia, which were being initiated in utero. This theme was expanded by Professor George Knox in his recent study which found that children born in “pollution hotspots” were two to four times more likely to die from childhood cancer. The “hotspots” included sites of industrial combustion, and sites with higher levels of particulates, VOCs, nitrogen dioxides, dioxins and benz(a)pyrenes – in other words just what would be found around incinerators. He said that, in most cases, the mother had inhaled these toxic substances and they were then passed on to the foetus through the placenta268. This is supported by animal studies which have already confirmed that cancer in young can be initiated by giving carcinogens before conception (to the mother), in utero or directly to the neonate269,270.
Developing systems are very delicate and in many instances are not able to repair damage done by environmental toxicants271. In one study there was an age-related difference in neurotoxicity for all but two of 31 substances tested; these included heavy metals, pesticides and other chemicals272. Children are not just a vulnerable group but the current inhabitants of a developmental stage through which all future generations must pass. This fact is recognised in the passage of the Food Quality Protection Act in the USA. It requires that pesticide standards are based primarily on health considerations and that standards are set at levels which will protect the health of children and infants.
Developmental disorders including autism and attention deficit syndrome are widespread and affect 3-8% of children. The US National Academy of Sciences concluded in July 2000 that 3% of all developmental disorders were a direct consequence of toxic environmental exposures and another 25% are the result of interactions between toxic exposures and individual susceptibility. The causes included lead, mercury, PCBs, certain pesticides and other environmental neurotoxicants273, substances that are all discharged from incinerators
Recently associations have been reported in case control studies between the body burden of mercury and the risk of autism274. In other studies in Texas, associations have been found between the amount of mercury discharged into the air and water by chemical plants and the local incidence of autism80 and an inverse relationship between the distances of schools from the plants discharging mercury and autism in their youngest pupils 4 years later; this is the lag expected from the fact that the greatest sensitivity to neurotoxicity is seen before birth and in neonates81. This suggests that mercury could be responsible but the contribution of other neurotoxins was not excluded.
The study of the Sint Niklaas incinerator found a multitude of problems in children, including learning defects, hyperactivity, autism, mental retardation and allergies95 and this is exactly what would be anticipated from the above and research already done on the health effects of heavy metals, PCBs and dioxins on children. Animal studies show similarities, with a recent study demonstrating autistic-like behavioural changes in rats whose mothers has been exposed to PCBs whilst pregnant; they had developed abnormal plasticity in the cortex of the brain275.
We need also to consider subclinical toxicity. The pioneering work of Herbert Needleman showed that lead could cause decreases in intelligence and alteration of behaviour in the absence of clinically visible signs of toxicity92. This has also been shown to be the case with PCBs276 and methyl mercury79. These effects are all the more likely when children are exposed to multiple pollutants, notably the heavy metals, which will be found in the cocktail of chemicals released by incinerators.
Although this has only minor implications for an individual it can have major implications for a population. For instance a 5 point drop of IQ in the population reduces by 50% the number of gifted children (IQ above 120) and increases by 50% the number with borderline IQ (below 80)277. This can have profound consequences for a society, especially if the drop in IQ is accompanied by behavioural changes.
6.4 The Chemically Sensitive
In the book, Chemical Exposures, Low Levels and High Stakes by Professors Ashford and Miller151, the authors noted that a proportion of the population react to chemicals and pollutants at several orders of magnitude below that normally thought to be toxic. For example research has discovered individuals who react to levels of toxins previously considered to be safe. Two examples are benzene278 and lead93. It has been demonstrated that there is a tenfold difference between different individuals in the metabolism of the carcinogenic PAH benz(a)pyrene279.
Ashford and Miller also noted that studies in both toxicology and epidemiology have recognised that chemicals are harmful at lower and lower doses and that an increasing number of people are having problems. A significant percentage of the population have been found to react this way (15 to 30% in several surveys with 5% having daily symptoms).151 Research has shown 150 to 450 fold variability in response to airborne particles280. Friedman has stated that environmental regulation requires the protection of these sensitive individuals281. This highlights the dangers of incinerators which emit a multitude of chemical compounds. Chemical sensitivity is typically triggered by an acute exposure after which symptoms start to occur at very low levels of exposure151. Faults are all too common with modern incinerators leading to discharges of pollutants at levels that endanger health – giving a very real risk of long-term sensitisation. Certain susceptible individuals will be highly affected by these pollutants and these effects will be difficult to anticipate. In addition, people affected this way are extremely difficult to treat.
7. Past Mistakes and The Precautionary Principle
7.1 The Precautionary Principle
The Precautionary Principle has now been introduced into national and international law including that of the European Union282. This principle involves acting in the face of uncertain knowledge about risks from environmental exposures. This means public health measures should be taken in response to limited, but plausible and credible, evidence of likely and substantial harm283. It is summed up in the 1998 Wingspread statement: “When an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically. In this context, the proponent of the activity, rather than the public, should bear the burden of proof.” In the case of incinerators a recent review of health effects found two thirds of studies showed a positive exposure-disease association with cancer (mortality, incidence and prevalence)284 and some studies pointed to a positive association with congenital malformations. In addition without exact knowledge of what pollutants are produced by incinerators, their quantities, their environmental fate or their health effects, it is impossible to assure their safety. It is absolutely clear from this and from the evidence presented here that building municipal waste incinerators violates the Precautionary Principle and perhaps European Law.
Time and time again it has been found that what we did not know about chemicals proved to be far more important than what we did know. As an incinerator generates hundreds of chemicals, including new compounds, we can expect many unpleasant future surprises. Here are a few examples from the past:
Автор: д-р социологии (PhD), к э н. Олейник А. Н. (Associate Professor Университета «Мемориал», Канада и с н с. Института Экономики...
«Технология продовольственных продуктов по отраслям» необходимые для обучения в PhD докторантуре и получения академической степени...
В докторантуре осуществляется подготовка докторов философии (PhD) и докторов по профилю (DS)